Selectively actuated well tool



Oct. 1, 1963 w. e. OWNBY SELECTIVELY ACTUATED WELL TOOL 4 Sheets-Sheet 1Filed March 30, 1959 VV. 6. Ownby INVENTOR. BY Q Q. 1%

A Trap/v5 V Oct. '1, 1963 w. G. 'OWNBY SELECTIVELY ACTUATED WELL TOOL 4Sheets-Sheet 2 Filed March 30, 1959 ATTORNEY 4 Sheets-Sheet 3 W INVENTOR.

W. G. OWNBY SELECTIVELY ACTUATED WELL TOOL /v/ a? am m 5 Z .6 /2\\\ w f.7///// v v////// 5 Oct. 1, 1963 Filed March 30, 1959 x I i 7///////n//fin a a ATTQRNEY Oct. 1, 1963 w. G. OWNBY 3,105,547

SELECTIVELY ACTUATED WELL TOOL Filed March 30, 1959 4 Sheets-Sheet 4 l 2BY A Tram/f Y United States Patent 3,165,547 SELECTIVELY ACTUATED WELLTUGL warren G. Ownhy, Houston, Tex., assignor to Cameo, Incorporated,Houston, Tex., a corporation of Texas Filed Mar. 30, 1%59, Ser. No.803,049 32 Claims. ((32. 166-65) This invention relates to well toolsand more particularly to an improved wire line type of equipment to belowered into a well for automatic operation upon reachmg a preselecteddepth and the present application is a continuation in part of pendingapplication Serial Number 778,826, filed December 8, 1958, nowabandoned.

An object of the invention is to provide a tool to be lowered into awell and to carry a signal detector which responds to a given signal intriggering the performance of an operation at a selected depth.

A further object of the invention is to provide an imroved tool havingseveral signal detectors co-operatively dependent on one another tocontrol a work performing operation upon their simultaneous responses toSignals received at a given location.

Another object of the invention is to employ several permanent magnetslocated in a well tubing string and arranged in sets at given depthstations and with the magnets of each set spaced apart in differentrelations and to use a lowering tool having magnetically actuatedswitches whose pole pieces are adjustable to key their relationselectively to any one of the sets of permanent magnets whereby theswitches act to close a control circuit under magnet influence in unisononly when they are in the magnetic fields of the selected set ofpermanent magnets, the completion of the control circuit serving totrigger a release of energy suitable for the job in hand.

A still further object of the invention is to enable the owner of a wellto install a series of spaced apart tool receiving nipples in a wellstring for the subsequent latching of a well working tool in any onenipple and -to associate with each nipple a magnetic field arrangementdifferent from the others and to which there can be coded the fielddetector of a tool lowering device so that latch actuation will beeffect at the proper moment for anchoring the tool in the desirednipple.

Another object of the invention is to provide an electro-mechanicallocating and actuating running tool having an electrically operated workperforming device connected in a control circuit containing a number ofseries connected switches responsive to radial disposition of tubingstring feelers or surface followers which are set in predeterminedaxially spaced apart relation coded or in correspondence to knownmechanical surface formations in a specim nipple incorporated at a givenlocation in a string of well tubing sections whereby when the locationof the nipple is reached by a tool being passaged through the string thefact will be signaled by transmission of feeler movement or displacementto close the several switches simultaneously and complete a circuit forcurrent flow to the work performing device.

In the accompanying drawing, illustrating preferred but not necessarilythe only embodiments of the invention, FIG. 1A is an elevational viewwith parts in section of the upper portion of a tool according to oneform; *lGS. 1B and 1C are elevations respectively showing anintermediate portion of the tool and a lower tool fragment and a hangerdetachably connected thereto, parts of the apparatus being in sectionand the tool being located in a well production string shown in section;FIG. 2 is a wiring diagram of the circuitry employed in the tool; FIG. 3is a vertical section of a well production conduit with the improvedtool located therein during a lowering operation; FIGS. 4A, 4B and 4Care vertical lid-$5,542 Fatented Got. 1, 1963 sectional viewsillustrating respectively an upper portion of a selectively actuatedwell tool, a lower portion thereof and a work performing devicesuspended therefrom with the lower part of FIG. 4C being in a largercasing; FIG. 5 is a vertical section corresponding generally to FIG. 4Bbut illustrating an alternative setting of the parts; FIG. 6 is atransverse section as on line 6-6 of FIG. 5; FIG. 7 is a wiring diagramof the circuit employed in the mechanical-electrical embodiment and FIG.8 is a perspective view with broken-away parts of a magnetic fieldsensing switch.

The usual well production conduit comprises a string of steel tubingsections including the section 1 in the drawing, and according to thisinvention certain of the tubing sections are specially formed with uppercounterbored ends of given length. Within the enlarged diameter uppercounterbored pocket of each of the several specially formed tubingsections and as seen in FIGS. 18 and 3, there will be fitted a series ofseparate rings including annular permanent magnets, spacer tubes forsetting the magnets at selected axial distances apart and nonmagneticnings, one on each side of each magnet. As illustrated, each pocket hastwo spaced apart magnets comprising an upper magnet 2 and a lower magnet3 so magnetized that their pole portions are radially inwardly andoutwardly thereof. On opposite sides of the magnet 2 are the rings 2a ofnonmagnetic material. Similar nonmagnetic rings 3:: are placed above andbelow the magnet 3. The lower set of rings 3 and 3a is hottomed on theshoulder at the lower end of the counterbore and separating the two setsof rings is a tubular spacer 4 of magnetic material. An upper spacertube 5, also of magnetic material, occupies the pocket above the uppermagnet ring. By installing spacer tubes 4 and 5 of varying lengths, theaxial spacing between the two magnets can be varied to provide any ofseveral distinctly different reference markers or detector signalingfields and according to the present invention, a number of sets ofmagnets are to be used at spaced apart depths as the station markers andthe spacing between the magnets of each set will be different, advantagebeingtaken of the spacing differences for selectively coding theretofield sensing detectors or magneto mechanisms for controlling theirsimultaneous responses.

The radially inward and outward faces of each permanent magnet ring areof opposite polarity and for the purpose hereof the inner face may beconsidered as a north pole and the outer or peripheral face may beconsidered as the south pole of the magnet. The magnetic field betweenthe poles is extended by the shields or guards afforded by thenonmagnetic rings above and below each magnet. Thus the how path extendsinto the tubing bore from the north pole and both upwardly anddownwardly around the nonmagnetic rings and through the tubing wall tothe south pole, and the field can be employed for a response in or tosignal operation of a magneto mechanism when the same traverses or isproperly brought into intersecting relation with the field.

Such response can be employed for effecting operation of work performingequipment of various kinds and an example of such operation is theactuation of a latch for securing a tool hanger in a landing nipple.Accordingly, the drawing illustrates a conventional tool hanger and atubular receiver or landing nipple 6 incorporated in the tubing string,and one of such nipples is immediately below each of several magnetcarrying tubing sections. That is to say, at a given distance below thelower magnet 3 of each magnet mounting tubing section, there will be alatch keeper notch 7 in a nipple 6.

The keeper notch 7, as seen in FIG. IC, has projected thereinto a numberof latch lugs 8 forming parts of a conventional tool hanger assembly andwhich comprises essentially a pair of telescopically fitted inner andouter concentric tubes 9 and 19. The innermost tube constitutes aslidable plunger having an annular carn ming enlargement 11 which upondownward retraction of the plunger 9 is brought into alignment with andprojects the latches 8 outwardly from their locating tube 10. Upwardprojection of the plunger 9 carries the carnming enlargement 11 abovethe latches 8 and enables their retraction from the keeper notch 7. Thusremoval of a previously latchedin tool hanger will necessitate the useof a wire line pulling tool which can be clutched onto a fishing neck atthe upper end of the plunger 9 for raising it upwardly, first permittinglatch retraction and then carrying the whole hanger assembly out of thewell.

Hanger installation is by means of a running tool arranged so that whenthe retracted latches come into alignment with a keeper notch of anipple at a preselected location, a controlled force can be applied fora relative downward projection of the plunger 9 in its housing 10.Thereaftenseparation of the running tool from the latched hanger can beeffected, for example, by breaking a shear pin connection 12 connectingthe upper end of the housing or outer tube with the lower end of therunning tool.

The running tool disclosed herein includes a wire line suspended hollowtubular barrel 13 housing plunger operating mechanism. Such mechanismincludes a slidable hammer or jar 14, shown by dotted lines in FIG. 1B,and which can be forced downwardly to strike the upper end of and topush down the hanger plunger 9. Hammer force may be supplied by variousagencies, including an energy storing spring held under stress by asolenoid releasable detent, but as illustrated in the drawing, therelease of operating energy is supplied by an explosive charge mountedin the chamber 15 above the hammer 14 and provided by a squib with anelectrically responsive firing cap. In the upper part of the runningtool there will be housed the electrical components arranged in acircuit as diagramed in FIG. 2 for firing the explosive charge or squib16.

in the wiring diagram, a main or manually set ofi and on switch 17 isshown in a position to open a control circuit and to close a groundingcircuit for the squib 16 as a safety factor against accidental ignition.When the device is ready for use and before it is lowered through thewell, the main switch 17 is thrown into engagement with a contact forclosing a circuit involving a battery 18 and a pair of oscillatory coils19 and 20 of magneto machines, the coils being in parallel and suppliedwith current from the battery 18 as controlled by variable resistances21 and 22. A switch having a fixed contact 23 and a movable contact 24is associated with the coil 19 and a similar switch comprising a fixedcontact 25 and a movable contact 26 is associated with the coil 24). Theswitches are series connected in a control circuit having therein abattery 27 and the coil of a relay switch 28. When both switches areconcurrently closed due to magnetic field responses at the coils 19 and20 as will be described, the relay switch 28 will be actuated forsupplying current from a battery 29 to fire the squib 16. The squib thusconstitutes an electrically responsive actuator for the explosive chargeor other work performing device and the switch assemblies constitutefield sensing or detector units since magnetic fields at the previouslymentioned station markers are detected or sensed by switch closingresponses upon tool traverse of the field.

The main switch 17 has its positions controlled by means of a set screw39 shown in FIG. 1A. This set screw is arranged for lateral adjustmentto move its tapered tip for position setting engagement with the conicalupper end of a head 31 on a switch actuating slidable stem 32 V normallyurged upwardly by a coil spring. When the screw is threaded inwardly,the switch 17 will be in the grounded relationship shown in FIG. 2 andwhen the screw 39 is backed outwardly, as seen in FIG. 1A, the

main switch will be in position for current flow in the circuit havingthe battery 18. The wiring for the various components corresponding tothose diagramed in the upper part of the circuit of FIG. 2, lead to aconnector panel 53 of FIG. 1A from which other wires lead downwardly tothe components represented in the lower half of the diagram of FIG. 2.

The coil 19 controlling the contacts 23 and 24 and the coil 20controlling the contacts 25 and 26 are parts of a pair of axially spacedapart magneto mechanisms located in the housing 13 and each mechanismalso includes two soft iron disks 33 and 34 spaced apart axially adistance which will approximate the vertical dimension of each of thenonmagnetic rings 2a and 311. Thus when any disk comes into transversealignment with any permanent magnet, the disk will constitute a polepiece or pole portion of the mechanism for co-operation with the innerface of the magnet and the field between the north and south poles ofthe magnet will be extended to include that pole piece and its companiondisk pole piece. In simplified form, FIG. 8 illustrates the magnetomechanism controlling the switch contacts 23 and 24. It includes theoscillatory coil 19 and co-operating field pole pieces arranged forcurrent flow from battery 18 through the coil so that whenever amagnetic field of proper polarity is extended across the coil windings,the coil will swing to close the contacts 23 and 24. The lower polepiece disc 34 has secured centrally of its upper face a transverse strapfrom whose opposite ends rise the two legs of an upstanding semicircularor inverted U-shape'd extension 35 which projects through peripheralnotches in and has clearance relation to the upper pole piece 33. Forconvenience of assembly, the upper pole piece 33 is formed as two halfsegments joined together and fixedly secured in insulated relation withthe bottom pole piece 34 and its upward extension 35. Within the spacesurrounded by the semicircular pole extension 35 and the upper polepiece 33 so as to be infiuenced by a magnetic field across the polepieces and wound on a pivotally mounted cylindrical core foroscillation, is the coil 19 in the form of a rectangular winding of fineWire whose opposite ends, as shown in FIG. 2, are in circuit connectionwith the battery 18. Supported by and movable with the oscillatory coil19 is the switch contact element 24 for co-operation with the fixedlypositioned switch contact 23 and these normally open switch contacts areparts of the control circuit (see FIG. 2) containing the battery 27.

When the master switch 17 is thrown for passage of current from thebattery 13 through the oscillatory coil 19, the switch contacts 23 and24 remain open except when the coil 19 is within a magnetic field ofproper polarity for influencing the coil 19 to swing, in acounterclockwise direction as viewed in FIG. 8, and shift the switchcontact 24 into closing relation with the fixed contact 23. Thisoperation is in accord with the principle of the dArsonval galvanometer.The upper magneto mechanism, including the coil 20 for circuitconnection with the battery 18 and the contacts 25 and 26 in the controlcircuit of the battery 27, is identical in arrangement and operation ofparts to the lower magneto mechanism just described and in conjoint usethe switches 23-24 and 25- 26 are in series connection in the controlcircuit of the battery 27.

In tool passage through the tubing string,a magnetic field of properpolarity to swing either coil into contact closing relation will beimpressed on the coil when its associated upper pole piece 33 comes intosubstantial alignment with the inner face or north pole of any permanentmagnet and at which time the lower pole piece 34 is in the flux pathtoward the magnet south pole. Because of the series connection of thetwo switches 2324 and 25-26, the magnetic field response of eithermagneto mechanism by itself fails to complete the control circuit of thebattery 27. Completion of the control circuit and closure of the relayswitch 28 in the firing circuit containing tne battery for the s acingbetween the u er oole ieces of the two sets to be coded or matched withthe spacing between the permanent magnets.

Dependency on the simultaneous alignment of upper pole pieces 33 or"both spaced apart sets with the spaced apart magnets in the tubingstring enables selective actuation of the control circuit at a givendepth since the two magnets in each of the several sets are spaced apartdifferently than those of other sets and only one set of magnets of thegroup will match the setting of the two pole pieces 33 for the toolcarried magnetically responsive coils. FIG. 3 shows a lowering toolpassing one set of magnets and having its pole pieces spaced differentlyfrom the magnets whereby their traverse of and response to therespective magnetic fields occurs at different times and the seriesconnection of the switches in the control circuit keeps the controlcircuit open and precludes operation of the firing circuit switch. Witha tubing string having a series of magnet containing or signalingstations, the magnetic switches can be coded to a particular one set ofmagnets by a presetting of the spacing between two upper sensing ordetector pole pieces for determining the release of the work performingenergy, whether at the first or other of the magnet sets in the tubingassembly.

For selectively setting the relative spacing of the ma netic switches tocoded relation with any set of magnets, there is here provided a novelcontrol or position selector means for adjustably varying the axialspacing between the two field infiuenced switch units. As shown, thelowermost unit is fixedly positioned by a screw stud 36 in FIG. 13,extending through a fixed insulator plate and into threaded engagementwith the lower pole piece 34. The upper magnetic switch is suspended bya U-shaped coupling 37 on the lower end of a rod 33 slidably mounted atits upper end in a reduced diameter opening through the housing. Thisupper end of the stem 33 has a series of axially spaced apart annulargrooves 39, any one of which can be brought into alignment with andreceive a projecting end of a set screw 49 threaded in the lateral borein the wall of the housing 13. The grooves 39 are uniformly spaced apartand the spacing is equal to the diiference in lengths betweensuccessively longer magnet spacing tubular members 4 of a set and whichare installed in any desired order beveen the magnets of the differentgroups. Thus it will be noted in FIG. 3 that the spacer 5 of the topmostgroup is of shorter length than the spacer 4 in the lowermost group ofmagnets illustrated. The spacing distance between the several grooves 39is followed in placing a number of magnetic inserts 41 through the wallof the housing 13 for alignment in all settings and contact with thepole pieces 33 and 34 for minimizing resistance in the magnetic fluxpath. Several vertical rows of such magnetic inserts preferably areprovided in circularly spaced apart relation.

To minimize fluid pressure differentials between the inside and theoutside of the housing 13 as might otherwise occur at different levelsand temperature conditions, the housing chamber enclosing the magneticswitches is preferably filled with a liquid, such as silicon oil, to alevel determined by a floating piston 42 at the upper end of the housingchamber, and a coil spring 43 exerts a light force downwardly on thepiston. A lateral port 44 through the wall of the housing communicatesthe chamber above the piston 42 with the outside of the casing for anequalization of pressure. submersion in oil of the delicate partsprotects them from inertia forces and improves electricalcharacteristics.

Inasmuch as the action of the earth as a magnet will induce magnetism ina piece of magnetic material projected vertically through the ground andwhose upper and lower ends are then of opposite polarity, it may befeasible in some installations and in place of permanent magnets, toemploy terrestial magnetism for the controlled actuation of the magnetomechanism. This would involve a tubing string including magnetic andnonmagnetic tubing sections of predetermined lengths coupled end to endand selectively in given order, whereby a signaling station isconstituted at a short nonmagnetic tube section which couples adjacentends of two magnetic sections. The separated but mechanically coupledends are then magnetic poles of opposite polarity and present a magneticfield from one to the other. Two such adjoining couplings will afford apair of spaced apart mag netic fields and several sets of differentvertical spacing can be incorporated in the tubing string, as in thecase of the permanent magnet installation.

As an alternative for signaling performance of work and completion of anelectric current flow control circuit through selective switch actuationin response to traverse of magnetic fields as heretofore described, thearrangement illustrated in FIG. 4B and its compan on views provides amechanical system for triggering release of energy when the running toolreaches a predetermined depth location during passage through the tubingstring. The illustrated mechanical switch actuating linkage is for usewith tubing string installations which incorporate internally groovednipples as commonly employed in sets of several spaced apart nipplesdifferently grooved and located at varying depths in a given well forQO-OPBIEtlOIl with various types of conventional well w rking toolsarranged for selective reception in the nipples. One of such nipples 51is shown in HS. 43 as m insert or tubing string section betweenadjoining lengths of the tubing string 52 and the nipple interiordiameter conforms generally to that of the other tubing string sectionsexcept for a pair of axially spaced apart internal grooves 53 and 5 5separated by a given length of land 55. The axial length of the land 55and/ or of each groove 53 and 54 will diifer in each of several nipplesin a string and will provide diseriminatorily dissimilar station markersor signaling devices at spaced apart depths. In making up the string,the nipples are assembled with tubing sections in selected order and foraxially spaced apart locations at predetermined final depths in the wellhole. Differing nipples in a set enable coding thereto of av workingtool to be run into the tubing string at any later time and includingmarker detector means for co-operation with a particular nipple.

For selective co-operation with a double grooved nipple 51, a runningtool as here proposed includes a wire line suspended body carrying anumber of axially spaced apart and radially movable feelers or tubesurface followers arranged to ride or track down the interior surface ofthe tubing string during tool descent and individually to move radiallyinwardly and outwardly as controlled by contact with surfaceirregularities or gaps in tube internal surface continuity. Relativeradial disposition of the feelers is utilized when all are in given.correlated settings as governed by alignment with groove and landformations or station markers of a selected nipple, for effectingsignaled responses to said reference markers and simultaneously closinga number of switches serially connected in an electric control circuitin completing the circuit and thereby eifecting a desired operation.

As shown in the drawing, the running tool assembly .56 comprises ahollow body or housing enclosing and mounting the several operatingparts and conveniently made up of an assembly of tubular members joinedin end to end succession. Primarily, the housing comprises a pair ofupper and lower tubes 57 and 58. The lower tube 58 has opposite endsinternally screw threaded for reception of end coupling plugs or spacersleeves 59 and 60 and the tube wall intermediate its ends has a set ofthree windows or axially elongated slots 6]; equally circumferentiallyspaced apart, as seen in FIG. 6. The upper housing tube 57 also isinternally threaded at opposite ends and receives coupling plugs 62 and63 (see FIG. 4A), of which the plug 62 terminates in a fishing neck 64,as well as a threaded stud similar to that shown at the top of FIG. 1A,by which a suspension wire line is to be connected. Another hollow tubeor tie rod 65 of smaller diameter than the lower tube 58 is nestedconcentrically within the lower tube and extends throughout the lengththereof and through and slightly beyond the spacing and coupling plug 60at the rod lower end and through and slightly beyond the spacing andcoupling plugs 59 and 63 at the upper tie rod end so as to becentralized within the tool :body 56. Clamping nuts 66, threaded onopposite ends of the central tube 65, bear on end faces of the couplingplugs 69 and 63 and hold the upper and lower tubes 57 and 58 inassembly.

A set of three axially spaced apart feeler and switch subassembly unitsare sleeved and mounted on the central tube or rod 65 and each includesone or more wall feeler members to extend through windows 61 in theouter tube 58. Three such feelers for each switch unit are contemplatedfor centering the running tool during its travel in .a tubing string.These subassemblies are generally similar but not necessarilyinterchangeable.

The uppermost unit includes a pair of axially spaced apart andrelatively movable tube embracing bands or collars 67 and 68interconnected by end to end pairs of swinging or folding shackle links69 having their remote ends hinged to the upper and lower collars 67 and68 and their adjoining ends pivoted on a trunnion pin or axle shaft fora rotatably mounted and tubing string engageable tracking wheel orfollower roller 70. The collar 67 threadably contains one or more setscrews 71 by which the collar is adjustably fixedly fastened to themounting tube 65 in a selected axial set position. Its companion collaror band 68 is free to slide or move axially toward and from the fixedcollar 67 as determined by lateral movement and position of the tubingstring follower wheel 70 as transmitted through the extensible shacklelinks 69. A microswitch 72 is bracketed or fixedly carried on thestationary collar 67 and contains a pair of contacts to be opened and,closed by a bridging blade a slidable nose projection for bearingabutment and movement with a post 73 on the slide collar 6%.

As previously indicated, the remaining two feeler and switch units aresimilar to that just described. The lowermost unit has a slide collar 74and an adjustably fixed collar 75 carrying a microswitch 76 whichoperating nose is engaged by an abutment on the slide collar and thecollars are interconnected by foldable motion transmitting linkageresponsive to follower 77 carried thereby. The intermediate unit has thefollower wheel 78 and motion transmitting linkage for controlling travelof a slide collar 79 relative to a fixed collar 3t? for opening andclosing the microswitch 81 mounted on the fixed collar.

A coil compression spring 82 surrounds the mounting rod 65 between theslide collars 68 and 79 of the upper and intermediate units andyieldably biases each collar toward its fixed mounting collar, or moreparticularly urges the interconnecting links and the feeler memberscarried thereby radially outwardly from an inwardly contractedrelationship. A spring coil 83 is interposed between the fixed collar 80of the intermediate unit and the slide collar 74 of the lowermost unitfor outwardly biasing the feeler members of the lowermost unit. Thesecoil springs 82 and 83 accommodate a range of relative axially spacedsettings of the adjustably fixed collars 67, 75

and 89 but springs of different lengthrmay be substituted 7 'to fitvarious spaced relations of the spaced apart units.

In the arrangement illustrated, the contacts of the intermediatemicroswitch 31 may be considered as normally closed and the contacts ofthe two endmost switches 72 and 76 may be considered as normally open;the normal relationship being that obtaining when the several feelermembers are in their radially contracted or laterally in ward positions.Thus, prior to the introduction of the running tool into a tubing stringand with all feelers free of radially restraint, all of them will beextended outwardly under the elastic force of the coil springs 82 andS3; wherefore the switches 72 and 76 are closed and the intermediateswitch 81 is opened. Upon insertion of the running tool into the tubingstring at the start of the lowering-in operation and when all feelersare contracted V by engagement with tubing string internal surfaces ofuniform internal diameter, the inward contraction of the feelers opensthe endmost switches 72 and 76 and closes the intermediate switch 81.

As the tool is run into the tubing, the several feelers 70, 7-7 and 78track on the tube interior and each will tend to move out as it comesinto alignment with any outward depression or clearance such as may bepresented at certain tubing joints and at nipple grooves or the like.Annular enlarged space at any region and which in axial dimension isless than the space between the endmost sets of feelers, on beingtraversed by the tool will enable each set of three teelers to drop outor extend into the radially enlarged space as each set in successiontraverses or comes into alignment with the space but no more than anytwo of the microswitc-hes will be closed at any instant during completetraverse of the space by the tool. Should any such annular clearancespace or outward tube depression be of greater axial length than thedistance between the endmost sets of feelers, then again at least onemicroswitch will be open throughout the traverse of the depression bythe three switches. In other words, if all three sets of feelers areexpanded coincidentally, the centermost switch 81 will be open and ifthe switch 81 is closed while either of the endmost switches 73 and 76has its feeler contracted, its associated microswitch will be open.However, if the spacing between the three sets of feelers is codedbeforehand for alignment to a particular double groovespacingarrangement of a given nipple 51, as illustrated in FIG. 413,then as tool descent brings the =followers into the relationship inwhich the centerrnost center feelers 78 engage the land 55 and arecontracted and the endmost feelers 7t? and 77 are extended into thegrooves 53 and 54, then all three micros-witches 72, 76 and 81 will beclosed. Therefore, regardless of tubing internal surface shape andirregular formations or diametrical variations, one or more of theswitches will be opened except when all three are positioned by theirfollower co-operation to a given nipple as in FIG. 4B.

Series connection of the several switches in a control circuit :iorelectric current fiow only when all three switches are concurrentlyclosed is contemplated for the performance of work at a predeterminedlocation, such as previously described for setting a hanger latchmechanism or for various other jobs, inclusive of a tube perforatingoperation. Circuit wiring of long distance extended clear back to thesurface is eliminated'by mounting a small battery or dry cell 84 withinthe upper housing tube 57, as seen in FIG. 4A. One terminal of thebattery may be grounded to the tool wall through a master switch 85containing contacts which are closed when a plunger 86 slidably mountedin theplug 62 is depressed by an inward adjustment of a stud S7 threadedthrough the plug wall and formed with an inner conical tip in cammingengagement with the upper terminal of the plunger 36. This main switch85, by manipulation of the screw stud 87, is adjusted to open positionat all times except in the interval between the start of a loweringoperation and the final removal of the running tool from a well. Theother battery terminal is joined by a arcane? conductor wire 88 extendeddownwardly through the tube 65 and passed through the wall of the tubefor connection with one contact of the uppermost switch 73. A shortlength conductor wire 89 joins the other contact of the uppermost switchwith one terminal of the centermost switch 81, whose other terminal isjoined by a conductor wire 90 with a contact of the lowermost switch 76.The remaining contact of the lowermost switch 76 is joined by aconductor wire 91 extended dot wardly for connection with a conventionalelectric plug connector at the bottom of the tube 65. Through the plugconnector, the control circuit may be continued to a suitable wc-rkperforming tool suspended from the well tool 56 and to be energizedwhenever the battery circuit is completed.

Devices which are coded, as in either embodiment previously described,for response to a selected tubing string insert are especially adaptedfor performance of perforating jobs through small diameter tubing. Forsuch usage, a conventional perforator 92 of either the bullet gun typeor shaped charge explosive type may be hung below the running tool, asin FIG. 4C, from an adapter 93 threadedly coupled to the lower end ofthe tube or tie rod 65 and from which extends a shielded or armoredconductor cable 94. One end of the conductor cable has a detachable plugconnection with the connector terminal 'of the conductor wire 91 forcurrent flow to the perforator 92 and from which the circuit iscompleted through the cable metallic shield to the grounded housing ofthe running tool 56. Suspension cable length is preselected to presentthe perforator at a distance below the running tool and microswitchassemblies to correspond with the distance between the region to beperforated and the tubing string nipple to which the series connectedswitches are coded for their concurrent closing of the control circuit.Thus, upon lowering of the perforator to a position opposite apreselected region of the tubing and the surrounding formation to bepierced, there will be completed automatically the control circuitthrough which current will be supplied for effecting the perforatingoperation. This control circuit, as previously described, is diagramedin FIG. 7 with the master switch S in its safety oil-position, with theintermediate switch 31 in its normally closed position and with theendmost switches 72 and 76 in their normally open positions.

in conventional oil and gas well completion practices, a string ofcasing is inserted and cemented throughout a substantial portion of thebore hole length during and immediately following the drilling operationand one or more narrow diameter tubing strings are run inside the casingand properly packed or cemented for Zone isolation and production.Thereafter, it is customary to make a combination radioactivity andcollar log to correlate pipe joints with the traversed formations andthen run a perforator through the tubing to a selected production zoneand actuate the per-forator to pierce through the casing and theformation and provide flow channels through which well fiuids can passfor production upwardly within the tubing string. If perforating can beperformed after the narrow tubing and its associated productionequipment at the surface have been set, then a relatively light fluidcan be employed instead of the ordinary heavy drilling mud normally usedto minimize blowouts but which also presents difficulties, andparticularly that of mud filter cake deposits which seal off theperforations. t is desirable, also, to be able to do workover jobs withequipment lowered through the narrow tubing under pressure for suchthings as supplemental perforating without th need for recirculatingheavy mud with likelihood of contaminating the formation. The equipmenthere described can be lowered through narrow tubing by means of a slick,small and solid wire line, and accurately perform perforating jobs underwell pressure. High accuracy of measurement is obtainable by a codedswitch actuation of a triggering nipple adjacent the zone to beperforated. More successful performance of perforating operations is tobe had than when measurements are referenced from the well head and aresubject to influences of cable stretch, frictional engagement with thewall surface and flotation conditions. Tubing string nipples to which arunning tool triggering mechanism may be adjusted or coded for actuationprovide a reference marker closely adjacent the zone to be worked.Marker location will be relatively permanent and determinable frominstallation records or detectable by simple collar locator tools whichalso can record a radioactive log for reliable depth location. The zoneof interest can be perforated by automatic response to running toolposition without dependence on observation of surface indications oftool travel or wire line suspension cable measurement.

What is claimed is:

1. Well working equipment to be passed through a well tubing stringhaving a number of station markers providing spaced apart of variouslyspaced apart magnetic fields extending into the interior space of thetubing string, said equipment including a tool to be passed through saidtubing string space, energy releasing means constituting a part of saidtool and having an activating device therefor responsive to the supplyof electric current to the evice, a current supplying circuit containingsaid device, switches in series relation in said circuit, switch closingmeans including magnetically responsive elements connected each to adifferent switch and means mounting said elements for relativeadjustment in the tool to spaced apart relations which correspond to thespaced relations of said variously spaced apart magnetic fields.

2. In combination, a tubing string, spaced apart pairs of permanentmagnets carried by the tubing string with the magnets of each pairspaced one from another a distance different from the space distancesbetween the magnets of other pairs, a tool to be passed through thetubing string and having an electrically actuated device therein, a pairof spaced apart switch closing elements responsive to the influencethereon of said magnets upon traverse thereof, means adjustably mountingsaid elements on the tool for relative adjustment of the spacingtherebetween to matched correspondence with the space distance betweenthe magnets of any of said pairs, normally open switches connected tothe elements respectively for switch closure upon magnetic response ofthe elements and a switch controlled circuit supplying current to saiddevice and containing said switches in series connection therein.

'3. Well working equipment including current actuated means, a controlcircuit therefor, a pair of magnetically actuated switches in seriesrelation in said circuit and each comprising a pair of co-operatingcontacts, a movable coil mounting one of the contacts for movementtherewith into engagement with the other contact and a pair of coilinfluencing pole pieces having spaced apart relation for exposure in amagnetic field, a switch containing housing to belowered in a well,means fixedly locating said switches in the housing with the pole piecesof one switch in given spaced relation with the pole pieces of the otherswitch. 7

4. Well working equipment as set forth in claim 3, wherein the switchlocating means includes a hired connection between one of the switchesand the housing and an adjustable connection between the housing and theother switch for selectively fastening the same to the housing in any ofseveral positions by which said given spaced relation of the pole piecesis established.

5. Well working equipment as set forth in claim 3, wherein the switchlocating means maintains the switches in vertically spaced apartrelation and includes a fixed connection joining the lowermost switch tothe housing, a post having one end vertically slidable in the housing, aset screw connection between the housing and post and operative to holdthe slidabie post in a selected position of vertical adjustment and afixed connection joining the uppermost switch on the lower end of thepost for movement with the post and the selective positioning of theuppermost switch relative to the housing.

6. Means for performing work at a preselected depth in a well, includinga well tubing string, a series of sets of permanent magnets mounted inthe wall of the tubing string in vertically spaced apart relation andwith the permanent magnets of each set vertically spaced from oneanother at a distance which is different in each set, a well tool havinga housing to he passed through the tubing string, electrically triggeredenergy releasing means carried by the tool, a control circuit therefor,spaced magnetically actuated switches, each adapted to be closed underthe influence of a magnetic field, series connected in said controlcircuit, vertically spaced apart pole pieces for the respective magneticswitches, means positioning said pole pieces in the housing forindividually traversing the fields of the permanent magnets successivelyduring passage of the housing through the tubing string, and adjustablemeans operable to set the pole pieces in various vertically spaced apartpositions a distance apart to correspond selectively with the verticalspacing of a given set of said permanent magnets for the unisonalmagnetic influencing of the series connected switches when their polepieces simultaneously traverse the permanent magnet fields of said givenset of permanent magnets.

7. Means for performing work in a well hole, including a well conduit, ahousing to be lowered in the conduit, an electrically actuated explosivecharge in the housing, a control circuit for firing said charge, a pairof spaced magnetically actuated switches, each adapted to be closedunder influence of a magnetic field, connected in series relation insaid control circuit and provided with pole pieces positioned by thehousing in vertically spaced apart relation and means in the wall ofsaid well conduit to present magnetic fields in the path of the housingand in vertically spaced apart relation corresponding to the verticallyspaced relation of said pole pieces.

8. The structure of claim 7, wherein the wall of the conduit has anumber of pairs of permanent magnets differently spaced apart and saidswitch pole pieces are mounted in the housing for relative adjustmentand can be preset to a vertically spaced apart relation incorrespondence with the spacing of a selected pair of magnets.

9. Means for performing work at a selected well depth, including atubing string having means therein at each of a number of depths topresent a pair of vertically spaced apart magnetic fields whose spacingdififers from that of the fields of other pairs, a housing to be passedthrough the tubing string, means in the housing inclusive of a source ofenergy, a control circuit, a pair of switches connected in series in thecircuit, separate magnetic field detector units connected one to eachswitch and operating to close such switch in response to magnetic fieldinfluence on the detector unit and means adjustably mounting saiddetector units in the housing and adjustable for setting the detectorspacing to match the spacing selectively of any pair of said magneticfields.

10. Means for performing work at any of several selected well depths,including a series of reference markers located at various depths in awell hole and each being comparatively dissimilar from the others, ahousing for passage through the well hole, electrically actuatedworkperforming means carried by the housing in an initially inactivecondition and means to activate said work a well hole including a numberof sets of spaced apart magnets positioned in the Well, magnetpositioning means maintaining the magnets of the several sets spacedapart differently in each set relative to the other sets and a tool tobe passed through the well, said tool comprising a housing, workperforming means carried by the housing and responsive to current flowin a control circuit therefor, a set of magnetic switches, each adaptedto be closed and r the influence of a magnetic field, connected inseries relation in the control circuit, a pair of pole pieces for eachswitch and means adjustably mounting the pole pieces in said housing toset the spacing therebetween to substantially correspond selectivelywith the spacing of the magnets in any of said sets.

12. Apparatus for the performance of work at any of several selecteddepths in a well including tubing string means located in a well, toolmeans to be passed through the well, a series of spaced apart poleportions carried by the tubing string means and arranged in sets of poleportions spaced apart diiferently in the several sets, a set of poleportions carried by the tool means and arranged for adjustment of thepole portions to spaced apart relations in substantial correspondenceselectively with the spacing of the pole portions in any of the severalsets carried by the tubing string means, means providing magnetic linesof force at and constituting functionally integral parts of the spacedapart pole portion carried by one of the means and magneto mechanism inmagnetic circuit connection with the pole portions carried by the othermeans and responsive to said lines of force upon extension thereofthrough the pole portions carried by said other means upon theirconcurrent alignment with the pole portions in any of the sets carriedby the tubing string means.

13. Well working equipment including a tubing string, a tool to bepassed through the tubing string, a work performing electricallyactuated device embodied in the tool for actuation at a selected depthwithin the tubing string, an electric control circuit for said devicecontaining a number of series connected switches mounted by said tooland arranged for individual switch closing action, a series of switchclosing and reference marker responsive detecting means, one for eachsaid switch, carried by said tool in given spaced apart relation and aseries of reference markers carried by said tubing string at adeterminable well depth location and spaced apart in coded relation tothe spacing of said last mentioned means for co-operation therewith ineffecting simultaneous response of the series connected switches.

14. Well working equipment as in claim 13 said reference markerscomprising a pair of internal groove s axially spaced apart apredetermined distance in a tubing string region at a known depth, andsaid reference marker responsive detecting means including radiallymovable feeler members, one for each switch, in motion transmittingconnection therewith whereby switch open and closed positions aredependent on the radial disposition of the feeler member, means mountingsaid feeler members on the tool to ride on the interior of said tubingstring during passage therethrough of the tool for controlling theradial disposition of the feeler members, said last mentioned meanslocating said feeler members in axially spaced relation corresponding tothe predetermined spaced apart distance between said internal groovesfor the coincident closing of said switches only when passage of t .etool through the tubing string reaches said tubing string region atknown depth.

15. The structure as in claim 14 wherein the means for mounting thefeeler members has a range of adjustment enabling selective variation inaxial spacing of the feeler members.

16. A well working tool as described in claim 13 for interchan eable usein difierent wells having tubing string nipples formed with axiallyspaced apart internal grooves to constitute said reference markers, saidreference marker responsive detecting means comprising a set of tubingstring engageabie feelers connected one with each switch for theactuation thereof and carried by the tool for movement radially thereofas controlled by tubing string engagement and adjustable mounting meansfor the feelers enabling variation in their axially spaced apartrelation to correspond selectively with the spacing of nipple grooves.

17. A well working tool as described in claim 16, together with biasingmeans active on and urging the feelers to move radially outwardly froman inwardly contracted position and wherein the number of feelerconnected switches includes two sets of switches with each switch of oneset being open when its feeler is inwardly contracted and each switch ofthe other set being open when its feeler is radially outwardly from itscontracted position.

18. A well working tool as described in claim 16 wherein saidelectrically actuated device is a perforating gun and is suspended apredetermined distance from the tool by means inclusive of a currentconductor in said circuit.

19. In combination, a well tubing string having a plurality of spacedapart stations, each conta ning a set of reference markers whosedisposition relative to one another is dissimilar to that of other sets,a work performing device for passage through the tubing string andactuation at a given location therein, a set of reference markerdetectors responsive individually to each marker or" all stationstraversed thereby, means mounting said detectors for their relativeadjustment with the device and enabling positioning of the detectors inselected relations corresponding with the relative dispositions of themarkers in the several sets and means responsive to marker detection byall the detectors in unison and connected with and active on said workperforming device to etfect its actuation.

20. A unit to be actuated at a selected locationupon movement through apassage having a number of stations comprising spaced apart sets ofseveral marker elements and having the elements of each set disposed incontrasting relation to those of other sets, said unit comprising a workperforming device, a control circuit therefor, a set of switchesconnected in series in said circuit, separate operating means for eachswitch including a station marker detector active to operate the switchin response to each station marker traversed by the unit and meanspositioning the detectors relative one to another in preset conformitywith the relative disposition of the marker elements of any setselectively for concurrent responses of the etector solely to themarkers of a selected set.

21. 'In combination; a tubing string, a plurality of permanent magnetscarried by the tubing string for the protuberance of separate magneticfields inwardly thereof and arranged in spaced apart sets and indifferent spaced apart relation in each set, a work performing tool forsuspended travel through the tubing string, tool carried means torelease working force and control mechanism therefor including anelectric circuit having series connected switches therein, separateactuating means for each switch responsive to magnetic field influencethereon and means for presetting the switch actuating means in spacedapart relation corresponding to spacing between the magnets of any oneset and for simultaneous response to the fields thereof to efiectconcurrent actuation of said series connected witches.

22. For signaling operation of a well tool being run through a welltubing string, a well tubing string section having an annular internalpocket, a succession of separate rings stacked within said pocket,magnets caried by certain of said rings and adapted to be selectivelyspaced apart by the disposition between magnet carrying rings of otherrings of predetermined axial lengths.

23. For signaling operation of a well tool being run within a welltubing string, a tubing string section, mounting means on said sectionfor locating a stack of spacer elements and magnetic field providingelements, a stack of such elements positionable by the mounting meanswith the elements in preselected succession, said elements beinginterchangeable for enabling variation in successive disposition of thespacer elements and the magnetic field providing elements.

24. For use with a well tubing string having a subsurface signalproviding marker and an internal latch keeper notch adjacent saidmarker, wire line equipment including a lowering tool adapted forlowering to said marker and a well tool adapted to be releasably coupledto the lowering tool and to be positioned thereby in the tubing string,said well tool comprising a tubular body, a laterally projectable latchshiftably mounted by the body for projection into and out of said keepernotch, a latch expander plunger axially slidably contained in the bodyand provided with latch engageable bearings controlling lateraldisposition of the latch and said lowering tool comprising an initiallyinactive force storing means arranged to release its stored force fortransmission to said plunger for sliding the same to latch projectingrelation, a marker signal responsive means rendering effective theaction or" said force storing means when the responsive mearis isbrought to the marker by a lowering operation and a releasable couplinginitiall joining said tools and being releasable in response to latchedWell tool resistance to movement with the lowering tool.

25. For use with a well tubing string having a series of stations atspaced apart depths and each providing a signal difierent in kind fromothers for co-operation selectively with and to signal actuation of atool assembly upon its passage through the tubing string, a toolassembly including a pair of separate tools capable of traversing saidstations, means releasably attaching the tools for support of one fromthe other and their passage as an assembly through the tubing string, aninitially retracted tubing string engageable anchor device carrie by oneof the tools and radially expansible for anchoring to the tubing string,force transmitting means operable to expand said anchor device, signalactuated means carried by the other tool and arranged to be set in codedrelation to and for actuation by any one selectively of the differentsignals, a releasable store of energy cooperating with the signalactuated means and responsive to signaled actuation thereof to supplyforce on the force transmitting means to expand said anchor device andsaid releasable attaching means being releasable upon movement of saidother tool relative to the tool which has been anchored to the tubingstring.

26. in combination, a well tubing string having a number of toolreceiving nipples therein, permanent magnets mounted by the nipples topresent inwardly protruded magnetic fields at spaced apart well depthlocations, a work performing tool adapted to be passed through thetubing string for traversing any desired number of said fields,releasable energy storing means carried by the work performing tool, afield sensing assembly mounted in the tool and operatively connectedwith the energy storing means to release the energy thereof in responseto magnetic field influence upon said sensing assembly and preset meansin the tool operative to condition the field sensing assembly andrestrict magnetic field response thereof to traverse by the tool of amagnetic field at a selected depth location. 27. In combination, a welltubing string having series of spaced apart latch assembly receivingsections each including an internal keeper groove for a latch dog andsignal means whose signal is distinctively unlike the signals of othersignal means in the tubing string, a running tool having a releasablework performing device responsive solely to the signal of a selectedsignal means, a latch assembly having a body releasably secured to therunning tool, a laterally projectable latch dog carried by the body andadapted for projection outwardly of the body and into said keeper grooveto latch the body against displacement both upwardly and downwardly, anda dog projecting plunger axially shiftably mounted in the body inco-operative relation with said work performing device for dogprojecting actuation thereby upon signaled release of the workperforming device, said tubing string sections, the running tool andsaid body all being devoid of locating abutments to interfere withtravel through the tubing string of said latch assembly prior to latchdog projecting actuation by signaled response of the work performingdevice.

28. For use with a Well tubing string having a series of spaced aparthanger anchoring sections each comprising a latch dog receiving keeperand signaling means whose signal is distinctly unlike the signals ofother signaling means in the tubing string and a running tool having areleasable work performing device responsive solely to the signal of aselected signal means for effecting anchoring of a hanger; theimprovement which includes a hanger body whose outside surface is devoidof external locating protuberances such as would limit free travel ofthe hanger through and beyond said hanger anchoring sections of a tubingstring, laterally propectable latch dogs carried by the body and adaptedupon projection into a keeper to latch the hanger body againstdisplacement both upwardly and downwardly and an axially shiftableplunger within the body provided with a latch dog engageable expanderformation to project the latch dog into a keeper upon plunger actuationby the signaled release of the work performing device.

29. In combination, a Well tubing string having a series of spaced apartmarker stations, each comprising a marker distinctly unlike the markersof other stations, a running tool for travel through the tubing string,a work performing device having actuator means responsive to electriccurrent supplied thereto and constituting a part of said running tooland electric rneans wholly contained Within and as a unitary assemblywith the running tool and comprised of a source of current and ohcuitmeans including switch means adapted to be closed and direct currentfrom said source to said actuating means, marker responsive meanscontrolling closure of said switch means and other means operable topreset the marker responsive means in responsive matching relation tothe marker of a selected one of said series of stations and for responsesolely to the selected marker.

30. For use in a well hole having a wall which contains a series ofsignaling stations each providing a set of inwardly protruding fields offorce vertically spaced apart and in given distance relation differentfrom the field spacing of other stations, an improved self containedtool to be run into the hole and comprising a housing, an electricallycontrolled work performing means carried by the housing, an electriccurrent supply circuit therefor containing normally open switch means,vertical- 16 ly spaced apart field responsive devices carried by thetool and operative on the switch means to close the same upon concurrentresponses of said devices to fields of force and a presetting means forselectively controlling the relative vertically spaced apart relation ofthe devices to match the field spacing at any signal station.

31. Means for performing work at any of several selected -well depths,including a series of stations, means locating said stations at variousdepths in a well hole, means at each station comprising a discriminatemarker comparatively dissimilar from the marker at the other stations, ahousing for passage through the well hole, work performing means carriedby the housing in an initially inactive condition and means to activatesaid Work performing means including energy storage means, markerresponsive mechanism having adjustable settings within the housing andcontrolling delivery of actuating energy from the storage means to thework performing means, and preselector means operative on sm'd mechanismand setting the same to discriminating relation with any one marker ofthe several stations whereby said mechanism is responsive only to thepreselected marker.

32. Well working equipment to be passaged through a well tubing havingspaced apart sets of variously spaced apart magnets providing magneticfields extending into the interior space of the tubing string, saidequipment including a tool to be passaged through said tubing space,work penforming means constituting a part of said tool and having anenergy responsive device :to activate the same, an energy supplyingcircuit containing said device, circuit completing means in seriesrelation in said circuit and including a set of magnetically responsivecontrol devices therefor, and means mounting said control devices forrelative adjustment in the tool to selected spaced apart relationscoinciding with the variously spaced apart magnetic fields of saidspaced apart sets.

References (Iited in the file of this patent UNITED STATES PATENTS2,147,544 Potts Feb. 14, 1939 2,228,623 Ennis Jan. 14, 1941 2,246,542June 24, 1941 2,350,832 Segesrnan June 6, 1944 2,476,136 Doll July 12,1949 2,476,137 Doll July 12, 1949 2,544,979 Brokaw et al. Mar. 13, 19512,550,004 Doll Apr. 24, 1951 2,729,494 Trobridge Jan. 3, 1956 2,741,316Long Apr. 10, 1956 2,768,684 Castel et al. Oct. 30, 1956 2,798,559 FreddJuly 9, 1957 2,862,564 Bostock Dec. 2, 1958 2,976,931 Dafiin Mar. 28,1961 3,619,841 Ternow Feb. 6, 1962 3,027,944 Feeser Apr. 3, 19623,032,107 Rumble et al May 1, 1962

10. MEANS FOR PERFORMING WOEK AT ANY OF SEVERAL SELECTED WELL DEPTHS,INCLUDING A SERIES OF REFERENCE MARKERS LOCATED AT VARIOUS DEPTHS IN AWELL HOLE AND EACH BEING COMPARATIAVELY DISSIMILAR FROM THE OTHERS, AHOUSING FOR PASSAGE THROUGH THE WELL HOLE, ELECTRICALLY ACTUATED WORKPERFORMING MEANS CARRIED BY THE HOUSING IN AN INITIALLY INACTIVECONDITION AND MEANS TO ACTIVATE SAID WORK PERFORMING MEANS INCLUDINGDETECTOR MEANS RESPONSIVE TO SAID MARKERS, AN ELECTRIC CURRENT SUPPLYCIRCUIT, SWITCH MEANS THEREFOR INFLUENCED BY THE RESPONSE OF SAIDDETECTOR MEANS TO CLOSE THE CIRCUIT TO THE WORK PERFORMING MEANS ANDMEANS OPERATIVE ON SAID DETECTOR MEANS TO SET THE SAME FOR RESPONSE TOANY ONE OF SAID REFERENCE MARKERS SELECTIVELY.
 22. FOR SIGNALINGOPERATION OF A WELL TOOL BEING RUN THROUGH A WELL TUBING STRING, A WELLTUBING STRING SECTION HAVING AN ANNULAR INTERNAL POCKET, A SUCESSION OFSEPARATE RINGS STACKED WITHIN SAID POCKET, MAGNETS CARRIED BY CERTAIN OFSAID RINGS AND ADAPTED TO BE SELECTIVELY SPACED APART BY THE DISPOSITIONBETWEEN MAGNET CARRYING RINGS OF OTHER RINGS OF PREDETERMINED AXIALLENGTHS.